Apparatus and method for ventral only ablation of the tongue

ABSTRACT

Apparatus and methods for ventral only ablation of the tongue, for use in treating sleep apnea and related breathing disorders. An RF ablation probe or wand is inserted in ventral surface of a patient&#39;s tongue in a superior plane along a longitudinal (i.e., anterior to posterior) axis of the tongue, to a predetermined depth. The wand is withdrawn, RF energy is applied, creating a lesion predominantly in the interior of the tongue in an anterior to posterior plane, thereby resulting in less scarring but appreciable movement of the posterior tongue base away from the posterior pharyngeal wall. Also disclosed is a tongue retractor device used for measuring the depth of wand insertion, lifting the tongue to expose the ventral surface of the tongue for the procedure, and providing a stop surface to inhibit further wand insertion.

This application claims the benefit of Provisional Application No.61/695,860, filed on Aug. 31, 2012, which is incorporated by referenceherein in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to medical apparatus andassociated methods, and more particularly to electro-surgical devicessuch as RF ablation devices, affiliated tools, and methods for treatingpatients suffering from sleep apnea.

BACKGROUND

Sleep Apnea is a sleep disturbance (disorder) characterized by abnormalpauses in breathing or instances of abnormally low breathing, duringsleep. An “apnea”, or basically a pause in breathing can typically lastfrom a few seconds to minutes, and may occur many times over a period ofan hour. In one form of sleep apnea, commonly known as the ObstructiveSleep Apnea (OSA), a patient's normal breathing is interrupted by aphysical block. As a result, not enough air reaches a patient's lungs,resulting in decreased airflow to the lungs, and consequently, snoring.Common symptoms of OSA include loud snoring, restless sleep, andconsequently, fatigue and sleepiness during the daytime. Further, apatient suffering from obstructive sleep apnea can also suffer a stroke.Even further, patients suffering from sleep apnea can have memory lossdue to reduced flow of oxygen to the brain caused by the decreasedairflow to the lungs.

Conventionally, continuous positive airway pressure (CPAP) is onetreatment for obstructive sleep apnea. CPAP treatments usually involve apatient wearing a mask or a similar device that fits over a patient'snose, or covering both the nose and the mouth of a patient. Usually, atube connects the mask to a motor that blows air into the mask throughthe tube. The air pressure can be adjusted based on the needs andcomfort level of the patient being treated. Generally it is the doctor'sresponsibility to decide what pressure setting is appropriate for thepatient. There are many available masks with many variations. But, manypatients have difficulty in tolerating forced air. Thus, claustrophobiaand feelings of suffocation and/or panic attacks are also frequentcomplaints for patients who are treated using CPAP. Masks can alsocreate sores, acne ulcers or annoying skin eruptions. Dry eyes fromleaky masks can also be one annoying condition.

Other methods of treatment of sleep apnea include nasal valves,surgeries (e.g., to remove and tighten tissue around the airway to thelungs), and dental devices. Such surgeries can involve tonguerepositioning, procedures concerning the patient's sinuses and valves,and various palatal techniques. However, surgeries can causemorbidity—pain and swallowing difficulties (i.e., patients have to be onsoft diet for long periods of time). Patients who have undergonesurgeries can also have difficulties in taste and speech. Also,conventional electrosurgical procedures cause deep thermal penetrationbecause of the high temperatures (usually, 400 degrees Celsius to 600degrees Celsius) used in the procedure. In many cases, even afterperforming surgeries, symptoms of sleep apnea can relapse after sometime. Moreover, surgical procedures, if at all, can be performed onadults who are able to undergo surgical procedures.

In one traditional method of treating sleep apnea, RF ablation (RFA)devices are used to create lesions (typically four or more) at the baseof the patient's tongue. Usually, such a method involves the doctortaking extra precaution so that the patient's lingual artery andhypoglossal and lingual nerves are avoided. The concept behind RFAinvolves dissociating soft tissue using bipolar radiofrequency energy.The devices comprise electrolytes in a conductive medium. A preciselyfocused plasma field (RF field) is created by exciting electrolytes inthe conductive medium. As a result, energized particles or ions in theplasma field get sufficient energy to break organic molecular bondswithin soft tissue at relatively low temperatures (usually, 40° C. to70° C.).

Traditional methods involving RF ablation devices for treating sleepapnea can be painful and can also result in undesirable healthcomplications of a patient. Examples of such complications includehematoma, dysphagia, dysarthria, deformity, aspiration, and otherundesirable complications. Consequently, patients treated usingtraditional RF ablation methods have to be hospitalized and intubated,thereby increasing medical costs and exposing patients to health risks.

Therefore, there is a long-felt but unresolved need for an improvedmedical device and associated tools and methods or procedures that treatsleep apnea without causing swelling or hematoma of a patient's tongue.Further, the improved procedure should cause significantly less pain toa patient, should preferably not involve intubation or hospitalizationof any kind. Even further, the procedure should result in reducedmorbidity arising from changes in swallowing. Also, the procedure shouldminimize the risk of relapse of the symptoms of sleep apnea.

BRIEF SUMMARY OF THE DISCLOSURE

Briefly described, and according to one embodiment, aspects of thepresent disclosure generally relate to RF ablation procedures,affiliated devices and tools to treat sleep apnea in patients. In oneembodiment, the ablation is generally performed on the ventral surfaceof a patient's tongue. Accordingly, the procedure as described herein istermed as Ventral Only Ablation of Tongue (VOAT), and is generally anoffice-based procedure without requiring hospitalization or intubationfor patients. In one aspect, the disclosed procedure is more effectivethan other tongue ablation techniques to move the posterior tongue baseaway from the posterior pharyngeal wall in patients suffering from sleepapnea, thereby creating more airway passage for allowing airflow to thelungs. In another aspect, the disclosed procedure is performed in asuperior plane along a longitudinal (i.e., anterior to posterior) axisof the patient's tongue. According to aspects as described herein, itwill be better understood from the following discussions thatcontraction resulting from the scarring induced by the procedure causesthe posterior tongue base to move away from the posterior pharyngealwall in patients suffering from sleep apnea.

These and other aspects, features, and benefits of the claimedinvention(s) will become apparent from the following detailed writtendescription of the preferred embodiments and aspects taken inconjunction with the following drawings and Exhibits, althoughvariations and modifications thereto may be effected without departingfrom the spirit and scope of the novel concepts of the disclosure.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings illustrate one or more aspects of thedisclosure and, together with the written description, serve to explainthe principles of the disclosure. Wherever possible, the same referencenumbers are used throughout the tables and exhibits.

FIG. 1 is a schematic cross sectional view of a patient undergoingtreatment according to aspects of the invention wherein theelectro-surgical instrument is shown inserted into the tongue via aninsertion point on the ventral surface of the tongue.

FIG. 2 is a schematic cross sectional view of a patient undergoingtreatment according to aspects of the invention wherein theelectro-surgical instrument is shown positioned for insertion into theventral surface of the tongue.

FIG. 3 is a front view of a patient undergoing treatment according toaspects of the invention wherein the electro-surgical instrument isshown positioned for insertion into the ventral surface of the tongue.

FIG. 4A is a schematic cross sectional view of a patient prior to theprocedure.

FIG. 4B is a schematic cross sectional view of a patient showingplacement of a retractor device on the tongue of the patent according toaspects of the invention before the tongue engaging portion of theretractor device has been slid forward to contact the ventral surface ofthe tongue.

FIG. 4C is a schematic cross sectional view of a patient showing theplacement of a refractor device on the tongue of the patent according toaspects of the invention after the tongue engaging portion of theretractor device has been slid forward to contact the ventral surface ofthe tongue.

FIG. 4D is a schematic cross sectional view of a patient showing theplacement of a refractor device on the tongue of the patient showing thetip of the electro-surgical device being inserted into the ventralsurface of the tongue through an opening in the tongue engaging portionof the retractor.

FIG. 4E is a schematic cross sectional view of a patient showing theelectro-surgical device fully inserted into the tongue and showing thetip of the device located at a predetermined distance from the terminalpoint on the dorsal surface of the base of the tongue.

FIG. 4F is a schematic cross sectional view of a patient showing theelectro-surgical device fully inserted into the tongue and showing thetip of the device located at a distance from the terminal point on thedorsal surface of the base of the tongue wherein energy is being appliedto tissue adjacent the tip of the probe.

FIG. 4G is a schematic cross sectional view of a patient showing theelectro-surgical device inserted into the tongue but withdrawn apredetermined distance from the terminal point, and showing the tip ofthe device located at a distance withdrawn from the terminal point onthe dorsal surface of the base of the tongue wherein energy is beingapplied to tissue adjacent the tip of the probe.

FIG. 5 is a side view showing placement of a refractor device on thetongue of the patient wherein measuring indicia are shown on the deviceand wherein the retractor portion of the device is slid forward tocontact the ventral surface of the tongue.

FIG. 6 is a schematic perspective view of a refractor device comprisingan elongate member having proximal and distal ends, a flattened regionat the proximal end which is bent downward for contacting a dorsalsurface at the base of the tongue, a handle adjacent the distal end, anda retractor extending from a clamp adapted to slide along the length ofthe elongate member wherein measuring indicia are shown along the lengthof the elongate member and illustrating how the refractor portion of thedevice can be slid back and forth along the length of the device.

FIG. 7 is a schematic side view of the retractor device of FIG. 6.

FIG. 8 is a schematic top view of the retractor device of FIG. 6.

FIG. 9 is a schematic back view of the retractor device of FIG. 6.

FIG. 10 is a schematic of an electro-surgical device comprising anelongate member having measuring indicia along the length of theelongate member and an adjustable stop adapted to engage the ventralsurface of the tongue or the tongue engaging portion of the refractor ofa retractor device thereby limiting the insertion depth of the tip ofthe electrosurgical device into the tongue of a patient.

FIG. 11 is a bar chart showing overall results of performing VOATprocedures on several patients.

DETAILED DESCRIPTION

For the purpose of promoting an understanding of the principles of thepresent disclosure, reference will now be made to the embodimentsillustrated in the attached Exhibits and drawings, and specific languagewill be used to describe the same. It will, nevertheless, be understoodthat no limitation of the scope of the disclosure is thereby intendedand any alterations and further modifications of the described orillustrated embodiments and any further applications of the principlesof the disclosure as illustrated therein are contemplated as wouldnormally occur to one skilled in the art to which the disclosurerelates. All limitations of scope should be determined in accordancewith and as expressed in the claims.

Aspects of the present disclosure generally relate to RF ablationprocedures, affiliated devices and tools to treat sleep apnea inpatients. In one embodiment, the ablation is generally performed byinsertion of an RF electro-surgical ablation device or needle into theventral surface of a patient's tongue.

There are various benefits of the Ventral Only Ablation of the Tongue(VOAT) procedure described herein. Examples of such benefits include,but are not limited to, quick recovery time, minimal risk to a patient'shealth, minimal incision, less sensitive incision, and nohospitalization or intubations. In particular, the VOAT procedure can beperformed in an office setting with reduced surgical support equipmentand personnel.

FIG. 1 is a schematic cross sectional view of a patient undergoingtreatment. As shown in FIG. 1, an elongate, needle-like electro-surgicaldevice 100 having a sharp tip 101 is inserted into the tongue 102 at aninsertion point 104 on the ventral surface of the tongue. As shown inFIG. 1, electro-surgical device 100 comprises a handle 106 and anelongate member 108 extending from the handle wherein the elongatemember has a proximal end 110 and a distal end 112 forming an insertiontip 101. As shown in FIG. 1, when the electro-surgical device 100 isfully inserted in the patient's tongue, distal end 112 is spaced adistance 122 from a terminal point 124 on the dorsal surface at the baseof the tongue.

As an alternative methodology for determining an appropriate insertiondepth for the procedure, considered in classic geometrical terms, FIG. 1also shows arrows 130, 132, which represent a distance of insertion ofthe electro-surgical device 100 into the tongue in an X-Y coordinatesystem, to as to provide a different frame of reference for insertion ofthe probe or tip. The lateral distance indicated by arrow 130 representsa desired insertion ventral insertion depth, anterior to posterior,relative to a premeasured lateral (X-axis) depth of the patient'stongue, while the vertical distance indicated by arrow 132 represented adesired insertion depth, superior to inferior plane, relative to apremeasured vertical (Y-axis) depth of the patient's tongue, measuredfrom the dorsal surface of the tongue, which as seen in the figure bearsa curvature or radius.

FIG. 1 thus shows the vertical or near-vertical (i.e., superior toinferior) plane 132 utilized in conventional RF ablation (RFA)procedures. Forming lesions in the tongue oriented in the superior toinferior plane 132 can cause more scarring. As described herein, inaccordance with aspects of the invention, lesions are formedpredominantly in the interior of the tongue in an anterior to posteriorplane 130. Less scarring results from forming lesions oriented in theanterior to posterior plane 130. Consequently VOAT procedures are moreapt to move the posterior tongue base away from the posterior pharyngealwall.

FIG. 2 is a schematic cross sectional view of a patient undergoingtreatment according to aspects of the invention wherein electro-surgicaldevice 100 is shown positioned for insertion into the ventral surface ofthe tongue at an insertion point 104.

FIG. 3 is a schematic front view of a patient undergoing treatmentaccording to aspects of the invention wherein the electro-surgicaldevice 100 is shown positioned for insertion into the ventral surface ofthe tongue at the insertion point 104.

FIGS. 4A-4G illustrate a method according to aspects of the inventionwherein a retractor device is used in conjunction with theelectro-surgical instrument, to assist in guiding the insertion of theelectro-surgical instrument or probe 100 and determine an appropriateinsertion depth. In this regard, FIG. 4A is a schematic cross sectionalview of a patient prior to the procedure showing the patient's tongue400.

FIG. 4B is a schematic cross sectional view of the patient showingplacement of a retractor device 402 on the tongue 400. The retractordevice 402 is used to lift the tongue to expose the ventral surface ofthe tongue and desired insertion point, maintain the tongue in a liftedposition to avoid interference or contact with the electro-surgicaldevice 100 during its use, contact with the dorsal surface 124 of thetongue, and provide a way or means to measure the patient's tongue forpurposes of determining an appropriate insertion depth for the RF probe.

As shown in FIG. 4B, device 402 includes an elongate member 404extending from a handle 406 having a distal end 408, a flattened region410 at the distal end 408 which is bent downward for contacting a dorsalsurface at the base of the tongue and a loop-like retractor portion 412extending downwardly from a clamp 414. As shown in FIG. 4B, clamp 414 isadapted to slide along the length of elongate member 404. Refractorportion 412 comprises a loop-like tongue-engaging portion 416 which isadapted to contact the ventral surface of the tongue near the insertionpoint when clamp 414 is slid forward toward flattened region 410.

As also shown in FIG. 4B, measuring indicia 418 are shown along thelength of the elongate member 404.

FIG. 4C is a schematic cross sectional view of a patient showing theplacement of a retractor device 402 on the tongue of the patient. Asshown in FIG. 4C, the clamp 414 of device 402 has been slid forward suchthat tongue engaging portion 416 contacts the ventral surface of thetongue. Preferably, the insertion point 104 is exposed within the areadefined by the loop of the tongue-engaging portion 416.

FIG. 4D is a schematic cross sectional view of a patient showingplacement of retractor device 402 on the tongue 400 of the patient andshowing the distal end 112 of electro-surgical device 100 being insertedinto the ventral surface of the tongue through an opening or insertionpoint 104 in the tongue-engaging portion 416 of the retractor device402.

FIG. 4E is a schematic cross sectional view of a patient showingelectro-surgical device fully 100 inserted into the tongue and showingthe distal end 112 of electro-surgical device 100 spaced at a distance122 from the terminal point 124 on the dorsal surface of the base of thetongue. According to some embodiments, distance 122 is 5-8 cm.

FIG. 4F is a schematic cross sectional view of a patient showingelectro-surgical device 100 fully inserted into the tongue 400 whereinradio frequency (RF) energy 420 is being applied to tissue adjacent thetip 101 at the distal end 112 of the electro-surgical device 100.Application of RF energy at the appropriate energy level results information of a lesion 425 within the cavity or void formed by insertionof the needle-like electro-surgical device.

According to aspects of the invention, the lesion 425 may be elongatedby gradual withdrawal of the electro-surgical device 100, while applyingRF energy, so as to form an elongate, axial lesion. FIG. 4G is aschematic cross sectional view of a patient showing electro-surgicaldevice 100 partially withdrawn (retracted) from the maximum extent ofinsertion in the tongue 400 as in FIG. 4F, wherein radio frequency (RF)energy 420 is applied to tissue adjacent the tip 101 at the distal end112 of the electro-surgical device 100 after an initial application ofenergy, with a subsequent application of energy to elongate the lesion425. Application of RF energy at the appropriate energy level results information of an elongated lesion 425 within the cavity or void formed byinsertion of the needle-like electro-surgical device 100. The elongatedextent of the lesion 425 may be controlled by the power settings of theelectro-surgical device, as well as the amount of withdrawal from themaximum extent, and also the application of discrete instances ofenergization followed by withdrawal a predetermined extent, in stages orsteps.

FIG. 5 is a side view showing placement of retractor device 402 on thetongue 400 of the patient, wherein measuring indicia or markings areshown on the device and wherein the retractor portion 416 of the deviceis slid forward to contact the ventral surface of the tongue. The distalportion 408 of the retractor device 402 contacts with the dorsal surfaceof the tongue 400.

FIG. 6 is a schematic perspective view of a retractor device 402. Asshown in FIG. 6, device 402 comprises an elongate member 404 having aproximal end adjacent a handle 406 and a distal end 408, a flattenedregion 410 at the distal end 408 which is bent downward for contacting adorsal surface at the base of the tongue, a handle 406 adjacent theproximal end, and a loop-like retractor 412 extending from a clamp 414adapted to slide along the length of the elongate member 404. Refractor412 includes a tongue engaging portion 416 which is depicted as an openloop in FIG. 6. The space 418 defined by the loop 416 provides a guidefor insertion of the electro-surgical instrument (not shown in thisfigure). The space 418 may be made smaller, as desired, or may include aseparate insertion guide (not shown) positioned within the space so asto facilitate and guide insertion of the electro-surgical instrument.

As also shown in FIG. 6, device 402 includes measuring indicia 418 alongthe length of elongate member 404. As shown in FIG. 6, clamp 414 andretractor portion 412 can be slid back and forth along the elongatemember 404 of device 402. In use, device 402 is placed on the tonguesuch that flattened region 410 is in contact with a dorsal surface atthe base of the tongue with clamp 414 slid backward toward handle 406.Clamp 414 and attached retractor portion 412 is then slid forward towardthe distal end 408 of device 402 until tongue engaging portion 410contacts the dorsal surface of the tongue. Once positioned and engagedon the tongue, device 402 can be used to manipulate and position thetongue into the proper position for the electro-surgical procedure. Theelectro-surgical instrument can be inserted through the open loop of thetongue engaging portion 416 of retractor portion 412.

FIG. 7 is a schematic side view of the refractor device 402 of FIG. 6.FIG. 8 is a schematic top view of the retractor device 402 of FIG. 6. Asshown in FIGS. 7 and 8, clamp 414 and retractor portion 412 can be slidback and forth along the elongate member 404 of the device. Inaccordance with one aspect, the clamp 414 can be moved to a differentposition 414′, thereby adjusting the position of the refractor portion412 to that shown at 412′. A holding means such as a set screw, ratchetand cog, compression clamp, elastic constrictor, or similar device maybe used to hold the clamp 414 in position after adjusting to thepatient's tongue.

FIG. 9 is a schematic back view of the retractor device of FIG. 6showing the open loop and space 418 formed by the retractor portion 412and tongue engaging portion 416.

FIG. 10 is a schematic of an electro-surgical device 100 comprising anelongate member 108 having measuring indicia 115 along the length of theelongate member 108 and an adjustable stop 117 adapted to slide alongthe length of elongate member 108. Adjustable stop 117 can also comprisea securing means (not show) such as set screw, ratchet, compressionclamp, elastic constrictor, etc. which allows the adjustable stop to besecured to elongate member 108 at a desired position. Adjustable stop117 can be used to limit the insertion depth of the tip 101 ofelectro-surgical device 100. In use, adjustable stop 117 can be set andsecured at a position to achieve the desired insertion depth into thetongue. According to one aspect, the insertion depth is the distancebetween the front surface of adjustable stop 117 and the tip 101 ofelectro-surgical device 100. As device 100 is inserted into the tongue,adjustable stop 117 will contact the ventral surface of the tonguethereby limiting the insertion depth of the tip of the electrosurgicaldevice into the tongue of a patient. Alternatively, the adjustable stop117 may contact the loop-like retractor portion 412 or guide of theretractor device 402 (see FIG. 4F, with stop not show), to preventfurther insertion.

An electro-surgical device 100 comprising an adjustable stop 117 asshown in FIG. 10 can also be used with a retractor device such as thedevice shown in FIGS. 6-9. When used with such a device, adjustable stop117 of electro-surgical device 1000 can be adapted to contact tongueengaging portion 416 of retractor portion 412 when the electro-surgicaldevice is inserted to the desired insertion depth.

The electro-surgical device 100 is preferably an RF ablation device. Thedevice can comprise a bipolar element on a 1-2 mm wide shaft, the shaftemitting a focused RF field (beam) for performing the VOAT procedure. Inone exemplary embodiment, such a wand is the Coblation™ Reflex 45manufactured by Arthrocare Corporation, in Austin, Tex. According toanother exemplary embodiment, a Celon Lab ENT wand and RF generatormanufactured by Olympus Medical Systems India, Olympus Corporation(Japan) can be employed.

As described above, the electro-surgical device 100 is guided intoposition to a predetermined distance 122 (FIG. 1) from the dorsalsurface of the tongue by measurement or by feel prior to puncture of thedorsal surface. Although puncture is preferable to avoid, it is notbelieved that puncture is a significant contraindication of theprocedure, and that the lesion formed from withdrawal may still beeffective.

According to another aspect, the tip 101 of the electro-surgical device100 can be guided into an appropriate position using other techniquessuch as RF image guidance such as a Fusion ENT Navigation Systemmanufactured by Medtronic, Inc., Minneapolis, Minn.

Exemplary details of steps involved in a VOAT procedure on a patientsuffering from sleep apnea are described in the discussions that follow.

According to an aspect, a VOAT procedure requires a patient to bemoderately sedated. Moderate sedation is induced with the assistance ofa nurse anesthetist or anesthesiologist. After sedation, the ventralaspect of the patient's tongue is exposed by retracting the patient'slower lip and jaw inferiorly, and the tongue posteriorly. Usually,sufficient tension is needed to spread out the mucosa over the undersurface of the tongue and submandibular gland duct openings.

According to aspects as described herein, the wand or probe of theelectro-surgical instrument 100 is positioned near the base of thetongue for puncturing the mucosa about 5-10 mm superior to thesubmandibular gland duct openings in the midline. After the mucosa ispunctured by insertion of the tip 101 of the wand, the wand is slowlyadvanced in the midline sagittal plane along the midline fusion plane ofthe tongue. The wand is typically set at a power level of 6 (in thepreferred Coblation™ Reflex 45) for 10 seconds, and held over a distanceof 5-8 cm from the base of the tongue. Advancing along the midlineavoids contact of the probe and radio waves in any significant fashionwith the arteries and veins of the tongue. Further, it also avoids thelingual and hypoglossal nerves.

The scarring or lesion created in the manner as described in the aboveprocedure has its longest axis in the anterior and posterior dimensionof the tongue, as opposed to the more vertically oriented lesions (SeeFIG. 1). It will be understood and appreciated that the contraction ofthe scar (caused due to the radiofrequency induced scarring) reduces thephysical blockage to the airway passage, thereby opening up the airwaypassage to the patient's lungs. Therefore, scarring according to VOATprocedure described herein is less than in previously described verticalplanes (e.g., see FIG. 1). Also, there is no significant bleeding,according to this procedure.

In the discussions that follow, patient data as a result of performingVOAT procedure are discussed.

Patient data as a result of performing VOAT procedure on three differentpatients is described below. The three de-identified patents arereferred to by the initials “RJ”, “MT”, and “EG”. Before describingfurther details of these patients, metrics used in determining theseverity of sleep apnea is described. One index used in measuring sleepapnea is AHI.

Specifically, AHI is an index used to assess the severity of sleep apneabased on the total number of complete cessations (apnea) and partialobstructions (hypopnea) of breathing occurring per hour of sleep. Thepauses (that last for 10 seconds or more) in breathing are associatedwith a decrease in oxygenation of the blood. In general, the AHI can beused to classify the severity of sleep apnea (mild 5-15, moderate 15-30,and severe greater than 30).

The patient RJ is a 65 year old asthma patient having gastroesophagealreflux disease (GERD) OSA, and with CPAP intolerance. The patientexperienced nightly headaches. The patient had a surgery, i.e.,bilateral maxillary balloon sinuplasty. However, OSA continued past hersurgery. VOAT procedures were performed on her twice over a three monthperiod. Prior to performing the VOAT, AHI levels were 15 events/hour.Post-VOAT levels were 1.1 events/hour. As a result, a 93% improvement inAHI levels, as a consequence of the VOAT procedure was recorded. CPAPtreatments were discontinued for this patient.

Patient MT had an initial AHI of 105. After CPAP, conditions were worseand patient did not want tracheostomy. Patient had previously undergonetongue resection palate and hyoid suspension procedures. The patient'sAHI of 87.9 was still uncontrolled with CPAP. After five in-office VOATprocedures, the AHI levels for this patient dropped to 41 and were 100%controlled with Bi-level Positive Airway Procedure (BIPAP). VOATsupplemented with a Bi-level Positive Airway Procedure (BIPAP) wastherefore able to control the sleep apnea of this patient by 100%.

Patient EG was CPAP intolerant and had a pre-VOAT AHI level of 29.9.However, post-VOAT AHI was measured as 0.9 for this patient.

Overall results of performing VOAT procedures on several patients wereevaluated. Only one (1) out of 300 patients who had VOAT procedures wasexposed to morbidity. Also, only one (1) patient out of 300 patients hada small anesthetic area tongue. Only two (2) patients out of 300 who hadVOAT procedures were exposed to minor bleeding.

FIG. 11 is a bar chart showing overall results of performing VOATprocedures on several patients. As shown in FIG. 11, average changes inAHI, pre-VOAT and post-VOAT, are indicated. In what follows, exemplaryaffiliated tools used in VOAT procedures (e.g., along with the RFablation device) are described.

EXPERIMENTAL DATA

The practice of this invention can be further understood by reference tothe following examples, which are provided by way of illustration onlyare not intended to be limiting.

Study Design:

Retrospective consecutive case series of 15 patients treated withventral only ablation of the tongue (VOAT) with comparison of pre andpost-operative polysomnography (PSG) results are discussed.

Setting:

Private practice otolaryngology clinic.

Subjects and Methods:

98 consecutive patients' records were reviewed. Patients who werereferred for intolerance of continuous positive airway pressure therapy(CPAP) therapy, and who were subsequently treated with radiofrequencyablation of the tongue base were included and records reviewed. Patientswho did not have their post-operative polysomnography (PSG) data wereexcluded as were any patients with concurrent interventions. Fifteen(15) patients were identified with these criteria and their AHI, and preand post operatively were compared.

Results:

The average pre-operative AHI of 34.2, post-operative average AHI of9.98 were significantly different with a p of 0.002. The averageimprovement in AHI was 24.34 or (72.3% improvement). Three patients(20%) failed to improve significantly. Overall complication rate 300procedures reviewed showed three patients who required observation forminor bleeding and one patient with long term tongue tip numbness.

Conclusion:

VOAT modification of the radiofrequency submucosal ablation of thetongue is a viable alternative to the current technique with minimalmorbidity.

According to an aspect, VOAT is a less-invasive variation of theradiofrequency ablation of the base of tongue procedure (RFA BOT). Anadjunctive treatment alternative for mild to moderate or severe OSA istherefore proposed.

Introduction:

CPAP remains the gold standard for OSA, but 29-83% of patients are CPAPintolerant or non-compliant [1, 2]. Surgical therapy for obstructivesleep apnea has been attempted with a variety of procedures. Nasalprocedures are a prerequisite to success if nasal obstruction ispresent. The pharyngeal level obstructions are more problematic.Tonsillectomy and adenoidectomy are appropriate for a minority of adultOSA patients. Uvulopalatopharyngoplasty (UPPP) is a significantly morbidoperation and, although commonly performed, is only effective for aminority of the OSA population. UPPP only has a success rate of 49%after 7 years with 30% of patients reporting swallowing difficulties[3]. Hyoid suspensions require a 2-5 day hospital stay and carry post opcomplaints regarding taste, speech, swallowing, and pain [4]. Nasalprocedures are appropriate as needed to improve nasal function and openthe airway. They are commonly performed but have not been able to show asignificant impact on adult OSA3. Maxillofacial surgery is as effectiveas CPAP but has a significant post op course requiring 6 weeks of softdiet [5].

Within the last decade, there has been an increasing use of RFA BOT tohelp alleviate the need for more invasive surgery as part of amultilevel pharyngeal treatment for sleep apnea. The technique, as it isgenerally described, involves placing a series of 4-5 lesions across thetongue base in a more or less superior inferior plane. The techniquerelies upon tissue heating, death, scarring and eventual contracture toachieve volume reduction at the tongue base.

RFA BOT results are reported to yield a 31% reduction in short term (<12month) and 45% reduction in long-term (>24 month) for respiratorydisturbance index (RDI) levels [6]. Controlled study of treatmentschemes for RFA suggests additional improvement in outcomes withrepeated treatments [7].

The current RFA BOT method has some drawbacks which include possiblebleeding from branches of the lingual vascular complex midline which cancause swelling and potential airway problems. The vascular structures atthis level cannot be identified readily from surface landmarks at thislevel.

Additionally, the lesions' long axis of contracture and thus volumereduction is in a superior and inferior orientation. This theoreticallyresults in less opening of the pharynx than if the lesions were anteriorto posterior orientation. Additionally, there is the concern of havingthe adjacent lesions creating circumferential contracture of the pharynxat the tongue base level.

This application describes a modification of the FDA approved RFAprocedure which addresses these issues and which can be performed in theoffice setting and the results of a case series review.

Subjects and Methods:

Consecutive cases from private practice were identified by computerizedsearch using the electronic medical records software and CPT codes.Ninety-eight (98) records were identified. All 98 patient records werereviewed for complications and the number of procedures performed.

From the 98 patient records identified, patients were excluded who hadany other procedure performed or any in the interval between pre- andpost-VOAT PSG, and those who had not completed postoperative andpreoperative PSG. This yielded 15 patients with PSG data before andafter treatment with only the VOAT therapy. Information was reviewed forBMI before and after procedure, number of VOAT procedures and subjectivedata including ESS. All PSG data was reviewed to ensure the laboratoryand reading physicians were using AASM criteria. Compiled results weresubjected to Student's t-test. Institutional review board approval wasobtained.

Operative Technique:

The operative technique is standardized as follows. Moderate sedation isinduced with the assistance of a nurse anesthetist or anesthesiologist.The ventral aspect of the tongue is exposed by retracting the lower lipand jaw inferiorly and the tongue superiorly posteriorly. There issufficient tension needed to spread out the mucosa over the undersurface of the tongue and submandibular gland duct openings. The wand isused to puncture the mucosa about 5-10 mm superior to the submandibulargland duct openings in the midline. The wand is then slowly advanced inthe midline sagittal plane along the midline fusion plane of the tongue.Advancing along the midline avoids aterio-venous and neural structure ofthe tongue. Base of tongue ablation was accomplished utilizing theArthroCare Coblation Reflex 45 wand at a power level of 6 for 10 secondsand over a distance of 5-8 cm.

Results:

The average pre-operative AHI was 34.2 (standard deviation=23.8),post-operative average AHI of 9.98 (standard deviation=11.8). Student'st test results on pre and post-operative AHI data was significantlydifferent with a p of 0.002. The average improvement in AHI was 24.34 or(72.3% improvement). 3 patients (20%) failed to improve significantly.

Overall complication rate 300 procedures reviewed showed 3 patients whorequired observation for bleeding and 1 patient with long term tonguetip numbness. There were no significant cases of dysphagia. There wereno patients admitted for pain control.

Discussion:

The currently described VOAT modification shows significant reduction inapnea-hypopnea index (AHI) which averages 75% improvement in short termimprovement, which compares favorably with previously reported data onthe RFA BOT resulted in a 31% reduction in short term (<12 month)respiratory disturbance index (RDI) levels[6]. Although it comparesfavorably with previous reports, comparison using direct prospectivedata remains needed. From this data, one can reasonably conclude thatVOAT is an improvement on the patient's untreated status.

Controlled study of treatment schemes for RFA suggests additionalimprovement in outcomes with repeated treatments [7]. This is likely tobe seen with VOAT technique, but cannot be confirmed with the dataavailable. Conclusions made regarding comparisons between the twotechniques are also limited by small sample size in this current report.In addition, previous reports may have utilized a different generationof radiofrequency ablation hand piece, and therefore conclusions maysuffer from type one error due to differences in equipment.

The current method for RFA BOT has some drawbacks which include possiblebleeding from branches of the lingual vascular complex midline, whichcan cause swelling and potential airway problems. The vascularstructures at this level cannot be identified readily from surfacelandmarks at this level.

Additionally, the lesions created by the current RFA BOT technique havea long axis of contracture and thus volume reduction is in a superiorand inferior orientation. This theoretically results in less opening ofthe pharynx than if the lesions were anterior to posterior orientation.Hypothetically, there is the concern of having the adjacent lesionscreating circumferential contracture of the pharynx at the tongue baselevel.

These risks of the current technique may be potentially alleviated byoperating in the midline with the VOAT technique. The midline of thetongue has no significant neurovascular structures. Additionally, thelesions thus created by the ventral approach are along the axis of thegeniohyoid and genioglossus and thus in an anterior and posteriororientation. This should hypothetically open the oropharynx andhypopharynx more than the current RFA BOT.

Complication rates from the VOAT study are comparable to reportedcomplication rates in the literature for RFA BOT, 1% for this studycompared with the published rate ranging from 1% to 4.6% [8, 9].

As noted above there is minimal morbidity with this procedure, as istrue for current techniques for RFA BOT. Current FDA approved RFAcommonly operates in the superior inferior plane. The VOAT lesions arearranged in an anterior to posterior plane, designed to improvesuspension of the tongue and prevention of the tongue falling into theairway while the patient is supine. A prospective study with extendedfollow-up on RFA showed persistent improvements EDS and OSAS-QOL andmedian reaction time testing and apnea-hypopnea index [10]. Prior toconcluding that VOAT is an improvement over the current technique, suchdata must be collected with the VOAT procedure

The foregoing description of the exemplary embodiments has beenpresented only for the purposes of illustration and description and isnot intended to be exhaustive or to limit the inventions to the preciseforms disclosed. Many modifications and variations are possible in lightof the above teaching.

The embodiments were chosen and described in order to explain theprinciples of the inventions and their practical application so as toenable others skilled in the art to utilize the inventions and variousembodiments and with various modifications as are suited to theparticular use contemplated. Alternative embodiments will becomeapparent to those skilled in the art to which the present inventionspertain without departing from their spirit and scope.

REFERENCES

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What is claimed is:
 1. An electrosurgical apparatus for use in ventralonly ablation of the tongue, comprising, in combination: (i) retractordevice for immobilizing the tongue in connection with a ventral onlyablation of the tongue procedure, comprising an elongate membercomprising a proximal end and a distal end, the distal end of theelongate member angled downward to engage the dorsal surface of the baseof the tongue; a handle adjacent the proximal end of the elongatemember; a clamp adapted to slide along a first portion of the elongatemember adjacent the handle; a retractor portion attached to andextending downwardly from the clamp, the retractor portion comprising aproximal portion attached to the clamp and a distal engaging portionadapted to engage the ventral undersurface of the tongue when the clampis slid toward the distal end of the elongate member; and (ii) anelongate RF energy radiating member adapted for ventral insertion intothe tongue from the ventral undersurface of the tongue, the RF radiatingmember having a proximal end and a distal end, the distal end radiatingRF energy when inserted ventrally into the tongue; a handle adjacent theproximal end of the elongate member; and an adjustable stop selectivelysettable along the length of the elongate member for inhibiting furtherinsertion of the elongate member upon contacting of the retractorportion of the retractor device when inserted into the ventral surfaceof the tongue.
 2. The apparatus of claim 1, further comprising: linearindicia on the elongate RF energy radiating member for indicating thedistance between the adjustable stop and the distal end of the elongatemember.
 3. The apparatus of claim 1, wherein the elongate RF energyradiating member comprises at least one electrode for delivering energyto tissue adjacent the distal end of the elongate member.
 4. Theapparatus of claim 1, wherein the first portion of the elongate memberincludes linear measuring indicia, wherein the linear measuring indiciacan be used to determine the distance between the distal end of theelongate member and the tongue engaging portion of the retractorportion.
 5. The apparatus of claim 1, wherein the tongue engagingportion of the retractor comprises a first curved member adapted toengage a first region adjacent to one side the midline sagittal plane ofthe tongue and a second curved member adapted to engage a second regionadjacent the opposite side the midline sagittal plane of the tongue. 6.The apparatus of claim 1, wherein the first and second curved regionsform a single continuous loop.
 7. The apparatus of claim 1, wherein thedistal end of the elongate member comprises a flattened portion adaptedto engage the dorsal surface of the base of the tongue.
 8. The apparatusof claim 1, wherein the elongate RF energy radiating member has a bendat a distance from the proximal end to form an angle of 5 to 30°.
 9. Theapparatus of claim 8, wherein the distance is 2-6 cm.